Such a gear-jumping-proof positive-locking clutch is described in German Published Patent Application No. 1 101 172. This positive-locking clutch is used to connect a vehicle transmission shaft to an idler pulley rotatably mounted coaxially with the shaft. The positive-locking clutch includes an axially displaceable sliding sleeve having a bevel on which are supported locking balls which, due to a radial force component, can be displaced into radial depressions in the gear wheel with axial displacement of the sliding sleeve. When the positive-locking clutch is disengaged, the locking balls are arranged directly outside the depressions radially, i.e., in the same position axially as when engaged. Due to the resulting constantly present radial mobility of the locking bodies, this unfortunately results in transmission noise, which is perceived as unpleasant by occupants of the vehicle.
Furthermore, German Published Patent Application No. 39 30 173 describes a synchronizer device having a radially displaceable lock.
U.S. Pat. No. 5,651,435 describes a synchronizer unit with which a transmission shaft can be braked against the gearbox.
Furthermore, German Published Patent Application No. 198 39 154 describes a shiftable square-tooth clutch in which the loads on the square teeth in starting up are reduced. With this shiftable square-tooth clutch, one part of the clutch is provided with a spring force-loadable locking pin by which displacement of a locking ball out of a radial recess in a transmission shaft into an outer radial position is prevented when the clutch part is in an intermediate position. In this intermediate position, no torque transmitting connection is established between the second clutch part and an idler pulley to be coupled, i.e., the square-tooth clutch is in the disengaged position.
It is an object of the present invention to provide a gear-jumping-proof positive-locking clutch which does not cause any transmission noise when disengaged.